1. Field of the Invention
The invention is related to a light emitting device and more particularly to a semiconductor light emitting device.
2. Description of Related Art
With the evolution of photoelectrical technology, traditional incandescent bulbs and fluorescent lamps have been gradually replaced by solid-state light sources of the new generation, such as light-emitting diodes (LEDs). The LEDs have advantages, such as long lifespans, small sizes, high shock resistance, high light efficiency and low power consumption and thus, have been widely adopted as light sources in applications including household lighting appliances as well as various types of equipment. Beside being widely adopted in light sources of backlight modules of liquid crystal displays (LCDs) and household lighting appliances, the application of the LEDs have been expanded to street lighting, large outdoor billboards, traffic lights, ultra-violet (UV) curing and the related fields in recent years. As a result, the LEDs have been developed as the light sources featuring economic power consumption and environmental protection.
In a typical light emitting diode chip, in order to achieve a strain relief effect of stacked layers of semiconductor, a strain relief layer of a super lattice structure may be employed between the N-type semiconductor layer and the light emitting layer, and the so-called super lattice structure is, for example, formed by employing layers with two different materials alternately stacked. Such implementation has become a generally customary method for people of ordinary skill in the art, and the conventional technology is failed to achieve a breakthrough on this point.